Efeito da adição de butanol na biodegradabilidade da gasolina e do óleo diesel

The increase in the oil price and the current trend of using renewable raw materials for the production of chemicals renew the interest in the production of biobutanol that, produced by fermentation of agricultural raw materials, can be used as a component of gasoline and diesel. With the commercialization of new fuels, environmental damages due to spills can occur. Among other techniques, the clean-up of these contaminated areas can be achieved with bioremediation, a technique based on the action of microorganisms, which has the advantage of turning hazardous contaminants into non toxic substances such as CO2, water and biomass. Thus, bearing in mind the use of biobutanol in the near future as a gasoline extender and due to the lack of knowledge of the effects of butanol on the biodegradation of gasoline, this work aimed to assess the aerobic biodegradation of butanol/gasoline blends and butanol/diesel (20% v/v), being the latter compared to the ethanol/gasoline blend and biodiesel/diesel (20% v/v), respectively. Two experimental techniques were employed, namely the respirometric method and the redox indicator 2,6-dichlorophenol indophenol (DCPIP) test. In the former, experiments simulating the contamination of natural environments were carried out in biometer flasks, used to measure the microbial CO2 production. The DCPIP test assessed the capability of four inocula to biodegrade the fuel blends. In butanol/gasoline experiments the addition of the alcohols to the gasoline resulted in positive synergic effects on the biodegradation of the fuels in soil and...(Complete abstract click electronic access below)

Regolazione della pompa elettrica del carburante a bassa pressione: Analisi dell'impatto sul consumo specifico di un motore a combustione interna

The trend of CO2 emission limit and fuel saving due to the oil price increase and are important drivers for engines development. The engine auxiliary devices electrification (g.e fuel pump) is a way to reduce the energy consumption, because it becomes possible to control them depending on engine operation point, this kid of management can be applied to the electric low-pressure pump. Usually the fuel delivery is performed at the maximum flow rate and a pressure regulator discharges the exceeding fuel amount inside the rail (gasoline engine) or upstream of the high pressure pump (common rail diesel engine). In this work it has been investigated the fuel saving achievable through a proper control of the electric fuel pump on a small common rail diesel engine, and a control architecture is proposed. The aim was to maximize the fuel economy without any impact on pressure control in the engine transient conditions. L'andamento del limite di emissioni di CO2 e il risparmio di carburante dovuto all'aumento del prezzo del petrolio sono fattori importanti per lo sviluppo dei motori. I dispositivi ausiliari, come la pompa del carburante, sono un modo per ridurre il consumo energetico, in quanto diventa possibile controllarli a seconda del punto di funzionamento del motore, questo tipo di gestione può essere applicato alla pompa elettrica a bassa pressione. Solitamente la portata del combustibile viene eseguita alla portata massima e un regolatore di pressione si scarica la quantità eccedente di carburante all'interno del rail (motore a benzina) o a monte della pompa a alta pressione (common rail motore diesel). In questo lavoro è stato studiato il risparmio di combustibile ottenibile attraverso un adeguato controllo della pompa elettrica del carburante su un piccolo motore diesel common rail e viene proposta una architettura di controllo. Lo scopo è quello di massimizzare il risparmio di carburante, senza alcun impatto sul controllo della pressione nelle condizioni transitorie del motore.

Das Thema „Energie“ in der wissenschaftlichen Zukunftsforschung

Der Umbau der durch den Einsatz fossiler Energieträger dominierten Energiesysteme steht weit oben auf der politischen Agenda. Angesichts des fortschreitenden Klimawandels, der Ressourcenverknappung und des ökonomischen Aufholens der Schwellen- und Entwicklungsländer wird diese Frage immer dringlicher. Zahlreiche politische, gesellschaftliche, ökonomische und ökologische Herausforderungen sind mit diesem Umbau verbunden. Angesichts der Langlebigkeit der heute gebauten Infrastrukturen ergibt sich hieraus ein zentrales Feld für die wissenschaftliche Zukunftsforschung. Der Einsatz von Energieszenarios ist über Jahre erprobt und trotz zahlreicher methodischer und inhaltlicher Unsicherheiten bei der Erarbeitung der Szenariostudien bleiben sie unersetzlich – sofern sie wissenschaftliche Standards hinsichtlich der Wertneutralität und Überprüfbarkeit erfüllen. Auch in der geographischen Forschung findet sich das Thema „Energie“ wieder verstärkt auf der Agenda. Bereits vor dem Hintergrund der Ölpreiskrisen in den 1970er-Jahren setzten sich Geographinnen und Geographen mit Energiethemen auseinander – angesichts des anstehenden Umbaus der Energiesysteme wird auch wieder die Frage aktuell, inwiefern sich die Transformation des Energiesystems und die Raumstruktur gegenseitig beeinflussen. Dabei werden nicht nur inhaltliche Fragen aufgeworfen, vielmehr ist auch zu klären, wie sich das Thema „Energie“ in die etablierten geographischen Forschungsdisziplinen von der Klimageographie über die Wirtschafts- und Bevölkerungsgeographie bis hin zur Siedlungsgeographie eingliedern lässt. Die Ausführungen im vorliegenden Artikel gehen noch einen Schritt weiter und werfen die Frage auf, inwiefern sich durch die Verbindung geographischer Forschung und Energiethemen auch ein neues methodisches Experimentierfeld auftut. Konkret wird aufgezeigt, dass die Geographie verstärkt den Blick in die Zukunft wagen und sich von der Analyse rezenter Strukturen lösen sollte. Die Frage der zukünftigen Raumstrukturen angesichts des Umbaus der Energiesysteme ist von zentraler Bedeutung, unter Anwendung von Methoden der wissenschaftlichen Zukunftsforschung muss die Geographie hier antworten liefern.

Macroeconomic Rationality and Lucas' Misperceptions Model: Further Evidence from Forty-One Countries

Several researchers have examined Lucas's misperceptions model as well as various propositions derived from it within a cross-section empirical framework. The cross-section approach imposes a single monetary policy regime for the entire period. Our paper innovates on existing tests of those rational expectations propositions by allowing the simultaneous effect of monetary and short run aggregate supply (oil price) shocks on output behavior and the employment of advanced panel econometric techniques. Our empirical findings, for a sample of 41 countries over 1949 to 1999, provide evidence in favor of the majority of rational expectations propositions.

Transformation of the Financial Sector in Indonesia

Introduction : The source and deployment of finance are central issues in economic development. Since 1966, when the Soeharto Administration was inaugurated, Indonesian economic development has relied on funds in the form of aid from international organizations and foreign countries. After the 1990s, a further abundant inflow of capital sustained a rapid economic development. Foreign funding was the basis of Indonesian economic growth. This paper will describe the mechanism for allocating funds in the Indonesian economy. It will identify the problems this mechanism generated in the Indonesian experience, and it will attempt to explain why there was a collapse of the financial system in the wake of the Asian Currency Crisis of 1997. History of the Indonesian Financial system The year 1966 saw the emergence of commercial banks in Indonesia. It can be said that before 1966 a financial system hardly existed, a fact commonly attributed to economic disruptions like the consecutive runs of fiscal deficit and hyperinflation under the Soekarno Administration. After 1996, with the inauguration of Soeharto, a regulatory system of financial legislation, e.g. central banking law and banking regulation, was introduced and implemented, and the banking sector that is the basis of the current financial system in Indonesia was built up. 　　　The Indonesian financial structure was significantly altered at the first financial reform of 1983. Between 1966 and 1982, the banking sector consisted of Bank Indonesia (the Central Bank) and the state-owned banks. There was also a system for distributing the abundant public revenue derived from the soaring oil price of the 1970s. The public finance distribution function, incorporated in Indonesian financial system, changed after the successive financial reforms of 1983 and 1988, when there was a move away from the monopoly-market style dominated by state-owned banks (which was a system of public finance distribution that operated at the discretion of the government) towards a modern market mechanism. The five phases of development The Indonesian financial system developed in five phases between 1966 and the present time. The first period (1966-72) was its formative period, the second (1973-82) its policy based finance period under soaring oil prices, the third (1983-91) its financial-reform period, the fourth (1992-97) its period of expansion, and the fifth (1998-) its period of financial restructuring. The first section of this paper summarizes the financial policies operative during each of the periods identified above. In the second section changes to the financial sector in response to policies are examined, and an analysis of these changes shows that an important development of the financial sector occurred during the financial reform period. In the third section the focus of analysis shifts from the general financial sector to particular commercial banks’ performances. In the third section changes in commercial banks’ lending and fund-raising behaviour after the 1990s are analysed by comparing several banking groups in terms of their ownership and foundation time. The last section summarizes the foregoing analyses and examines the problems that remain in the Indonesian financial sector, which is still undergoing restructuring.

Análise do impacto das políticas de intervenção no setor do agronegócio sobre a cadeia de carne bovina na Venezuela

O objetivo deste trabalho foi analisar o desempenho da cadeia de carne bovina na Venezuela sob o efeito de políticas de intervenção estatal principalmente nas últimas décadas. Para tanto, foi empregada a abordagem teórica do enfoque sistêmico em conjunto com metodologia que se apoiou em um modelo econométrico para explicar o efeito de variáveis tecnológicas e macroeconômicas no agronegócio vis a vis a resultante da produção doméstica de carne bovina nas últimas décadas. Os resultados mostram que, no marco de mudanças institucionais estabelecidas desde a década de 1980 e especialmente as intervenções governamentais vigentes a partir do ano de 2003, a cadeia de carne bovina da Venezuela apresenta um desempenho negocial preocupante e não sustentável. Na última década, a Venezuela decresceu seu inventário bovino a uma taxa média anual de 2,56% entre 2003 e 2014. O número de cabeças/habitante diminuiu a uma taxa anual de 1,30% entre 1960 e 2014, ficando em 0,38 cabeças/habitante. O número de cabeças abatidas sobre o total do rebanho (taxa de desfrute geral do rebanho) foi de 10,82% para o ano de 2014, inferior à média de países vizinhos como Colômbia e Brasil que ficaram em 20,85% e 19,42% respectivamente. A produção doméstica de carne bovina decresceu a uma taxa anual de 2,22% entre 1997 e 2014 (mesmo considerando o abate de bovinos importados). A quantidade de carne oriunda de animais importados cresceu até alcançar um máximo de 58,51% do abate nacional, em 2013. Isto significou um decréscimo real da produção endógena de 71,55% entre os anos de 1997 e 2013. Neste contexto, a produção nacional percapita diminuiu de 18,31 kg/habitante (em 1997) para um mínimo de 3,97 kg/habitante (em 2013). Para o atendimento da demanda doméstica passou-se a contar, crescentemente, com importações de carne in natura que cresceram em volume inicial de 0,59 mil toneladas (t) de equivalente carcaça (em 1997) para um máximo de 307,57 mil t em 2008. A taxa de penetração das importações de carne bovina equivalente (carne e bovinos em pé) resultou em 79,54% do atendimento da demanda doméstica em 2013 (cerca de 15,45 kg/habitante/ano). Neste contexto, as intervenções mais relevantes têm sido a Lei de Terras que propiciou um ambiente de insegurança jurídica; os controles de preços e a política cambial que criaram distorções no mercado; e, a crescente influência nas redes de distribuição de alimentos, com forte dependência do comércio exterior, alavancado com os incrementos no preço internacional do petróleo entre 2003 e 2014. Tudo isto tem resultado em um cenário de desmonte da produção interna da carne bovina, que pode ser visualizado em episódios crescentes de escassez deste produto no mercado interno. Ao final, são sugeridas algumas práticas de políticas pública e setoriais para a reversão desse quadro insustentável para esta importante cadeia de negócios da Venezuela.

Inflation persistence in Central and Eastern European countries. Bruegel Working Paper 2013/04, 22 July 2013

This paper studies inflation persistence with time-varying coefficient autoregressions for twelve central European countries,in comparison with the United States and the euro area. Inflation persistence tends to be higher in times of high inflation. Since the oil price shocks, inflation persistence has declined both in the US and euro-area. In most central and eastern European countries, for which our study covers 1993-2012, inflation persistence has also declined, with the main exceptions of the Czech Republic, Slovakia and Slovenia, where persistence seems to be rather stable.

Low severity Fischer-Tropsch synthesis for the production of synthetic hydrocarbon fuels

Currently, the main source for the production of liquid transportation fuels is petroleum, the continued use of which faces many challenges including depleting oil reserves, significant oil price rises, and environmental concerns over global warming which is widely believed to be due to fossil fuel derived CO2 emissions and other greenhouse gases. In this respect, lignocellulosic or plant biomass is a particularly interesting resource as it is the only renewable source of organic carbon that can be converted into liquid transportation fuels. The gasification of biomass produces syngas which can then be converted into synthetic liquid hydrocarbon fuels by means of the Fischer-Tropsch (FT) synthesis. This process has been widely considered as an attractive option for producing clean liquid hydrocarbon fuels from biomass that have been identified as promising alternatives to conventional fossil fuels like diesel and kerosene. The resulting product composition in FT synthesis is influenced by the type of catalyst and the reaction conditions that are used in the process. One of the issues facing this conversion process is the development of a technology that can be scaled down to match the scattered nature of biomass resources, including lower operating pressures, without compromising liquid composition. The primary aims of this work were to experimentally explore FT synthesis at low pressures for the purpose of process down-scaling and cost reduction, and to investigate the potential for obtaining an intermediate FT synthetic crude liquid product that can be integrated into existing refineries under the range of process conditions employed. Two different fixed-bed micro-reactors were used for FT synthesis; a 2cm3 reactor at the University of Rio de Janeiro (UFRJ) and a 20cm3 reactor at Aston University. The experimental work firstly involved the selection of a suitable catalyst from three that were available. Secondly, a parameter study was carried out on the 20cm3 reactor using the selected catalyst to investigate the influence of reactor temperature, reactor pressure, space velocity, the H2/CO molar ratio in the feed syngas and catalyst loading on the reaction performance measured as CO conversion, catalyst stability, product distribution, product yields and liquid hydrocarbon product composition. From this parameter study a set of preferred operating conditions was identified for low pressure FT synthesis. The three catalysts were characterized using BET, XRD, TPR and SEM. The catalyst selected was an unpromoted Co/Al2O3 catalyst. FT synthesis runs on the 20cm3 reactor at Aston were conducted for 48 hours. Permanent gases and light hydrocarbons (C1-C5) were analysed in an online GC-TCD/FID at hourly intervals. The liquid hydrocarbons collected were analyzed offline using GC-MS for determination of fuel composition. The parameter study showed that CO conversion and liquid hydrocarbon yields increase with increasing reactor pressure up to around 8 bar, above which the effect of pressure is small. The parameters that had the most significant influence on CO conversion, product selectivity and liquid hydrocarbon yields were reactor temperature and catalyst loading. The preferred reaction conditions identified for this research were: T = 230ºC, P = 10 bar, H2/CO = 2.0, WHSV = 2.2 h-1, and catalyst loading = 2.0g. Operation in the low range of pressures studied resulted in low CO conversions and liquid hydrocarbon yields, indicating that low pressure BTL-FT operation may not be industrially viable as the trade off in lower CO conversions and once-through liquid hydrocarbon product yields has to be carefully weighed against the potential cost savings resulting from process operation at lower pressures.

A barrier and techno-economic analysis of small-scale bCHP (biomass combined heat and power) schemes in the UK

bCHP (Biomass combined heat and power) systems are highly efficient at smaller-scales when a significant proportion of the heat produced can be effectively utilised for hot water, space heating or industrial heating purposes. However, there are many barriers to project development and this has greatly inhibited deployment in the UK. Project viability is highly subjective to changes in policy, regulation, the finance market and the low cost fossil fuel incumbent. The paper reviews the barriers to small-scale bCHP project development in the UK along with a case study of a failed 1.5MWel bCHP scheme. The paper offers possible explanations for the project's failure and suggests adaptations to improve the project resilience. Analysis of the project's: capital structuring contract length and bankability; feedstock type and price uncertainty, and plant oversizing highlight the negative impact of the existing project barriers on project development. The research paper concludes with a discussion on the effects of these barriers on the case study project and this industry more generally. A greater understanding of the techno-economic effects of some barriers for small-scale bCHP schemes is demonstrated within this paper, along with some methods for improving the attractiveness and resilience of projects of this kind. © 2014 Elsevier Ltd.

On the Lp-Norm Regression Models for Estimating Value-at-Risk

Analysis of risk measures associated with price series data movements and its predictions are of strategic importance in the financial markets as well as to policy makers in particular for short- and longterm planning for setting up economic growth targets. For example, oilprice risk-management focuses primarily on when and how an organization can best prevent the costly exposure to price risk. Value-at-Risk (VaR) is the commonly practised instrument to measure risk and is evaluated by analysing the negative/positive tail of the probability distributions of the returns (profit or loss). In modelling applications, least-squares estimation (LSE)-based linear regression models are often employed for modeling and analyzing correlated data. These linear models are optimal and perform relatively well under conditions such as errors following normal or approximately normal distributions, being free of large size outliers and satisfying the Gauss-Markov assumptions. However, often in practical situations, the LSE-based linear regression models fail to provide optimal results, for instance, in non-Gaussian situations especially when the errors follow distributions with fat tails and error terms possess a finite variance. This is the situation in case of risk analysis which involves analyzing tail distributions. Thus, applications of the LSE-based regression models may be questioned for appropriateness and may have limited applicability. We have carried out the risk analysis of Iranian crude oil price data based on the Lp-norm regression models and have noted that the LSE-based models do not always perform the best. We discuss results from the L1, L2 and L∞-norm based linear regression models. ACM Computing Classification System (1998): B.1.2, F.1.3, F.2.3, G.3, J.2.

Die Interdependenz zwischen Europa und seinen Energielieferländern im historischen Kontext

von Alexander Smith

The Motif Tracking Algorithm

The search for patterns or motifs in data represents a problem area of key interest to finance and economic researchers. In this paper we introduce the Motif Tracking Algorithm, a novel immune inspired pattern identification tool that is able to identify unknown motifs of a non specified length which repeat within time series data. The power of the algorithm comes from the fact that it uses a small number of parameters with minimal assumptions regarding the data being examined or the underlying motifs. Our interest lies in applying the algorithm to financial time series data to identify unknown patterns that exist. The algorithm is tested using three separate data sets. Particular suitability to financial data is shown by applying it to oil price data. In all cases the algorithm identifies the presence of a motif population in a fast and efficient manner due to the utilisation of an intuitive symbolic representation. The resulting population of motifs is shown to have considerable potential value for other applications such as forecasting and algorithm seeding.

Simulador de dano à formação, aplicado ao Projeto e à execução da perfuração de poços de petróleo

With the high oil price variability, the petroleum and the reservoir engineers are usually face to face on how they can evaluate the well performance and productivity. They can improve high productivity from the well construction to the secondary recoveries, but they have never tried a measurement in the drilling operations about the lower productivity index. As a rule, frequently the drilling operations hear from the reservoir engineering and geology that, if there is a formation damage, probably some drilling operations practices were not done properly or the good practice in petroleum engineering or mud engineering were not observed. The study in this working search is an attempt of how to measure a formation damage just from the project drilling to the drilling operations, with datum from the fields in Brazilian northeast and putting into practice a Simulator developed from the modeling on the theory offered by different experts and sources in formation damage

Aplicaciones de los modelos de predicción bio-inspirados en la administración

Las organizaciones y sus entornos son sistemas complejos. Tales sistemas son difíciles de comprender y predecir. Pese a ello, la predicción es una tarea fundamental para la gestión empresarial y para la toma de decisiones que implica siempre un riesgo. Los métodos clásicos de predicción (entre los cuales están: la regresión lineal, la Autoregresive Moving Average y el exponential smoothing) establecen supuestos como la linealidad, la estabilidad para ser matemática y computacionalmente tratables. Por diferentes medios, sin embargo, se han demostrado las limitaciones de tales métodos. Pues bien, en las últimas décadas nuevos métodos de predicción han surgido con el fin de abarcar la complejidad de los sistemas organizacionales y sus entornos, antes que evitarla. Entre ellos, los más promisorios son los métodos de predicción bio-inspirados (ej. redes neuronales, algoritmos genéticos /evolutivos y sistemas inmunes artificiales). Este artículo pretende establecer un estado situacional de las aplicaciones actuales y potenciales de los métodos bio-inspirados de predicción en la administración.

How do Small Players Deduce Beliefs about Uncertainty? A Look at Texas Shale Oil Investments

Thesis (Ph.D.)--University of Washington, 2016-08